1. Technical Field
The present invention relates to an electronic component and a method of manufacturing the electronic component.
2. Related Art
A method of barrel plating is generally applied to forming a plated layer such as solder plated layer on a surface of a terminal electrode of an electronic component. In the barrel plating method, many electronic components are put into a basket dipped into a plating solution with metal grains called as dummy balls and plated by oscillating or rotating the basket and applying electricity to it. Even if dummy balls contact an insulating protective layer included in an electronic component, they do not contribute to plating layer formation. Hence, it is difficult to form a plating layer in an area of a terminal electrode close to the interface between a protective layer and a terminal electrode. As a result, a plated layer becomes thinned or unfinished in such area. This means that the area is exposed to the atmosphere, corroding the terminal electrode (a part including Ag in particular) with sulfur in the atmosphere.
In order to restrain such corrosion, JP-A-2004-253467 discloses the technology in that an auxiliary electrode is placed at the interface between a protective layer and a terminal electrode of a resistor element as a chip resistor device on a surface of a substrate where the resistor element is formed. The auxiliary electrode is connected to the terminal electrode.
On the other hand, other members of the resistor element such as a resistor member, a glass film for protecting the resistor member and the like are also placed on the surface of the substrate where the resistor element is formed. Hence, there is difficulty in that many members must be accurately arranged in a extremely narrow area if the auxiliary electrode further is placed at the interface between the protective layer and the terminal electrode.